如何在root用户和普通用户模式下在golang的vim中打开语法？

I modified ~/.vimrc and added the following line:

syntax on

to turn syntax on. The syntax is highlighted for python, java, but for golang it doesn't highlight at all.

I would like to do the same when editing vim files, logged in as root too. I tried to modify vimrc as root but none of the modes work with syntax.